2,149. The Severity of the Prohibition

Hilchos Issurei Biah 12:12

The Sages didn’t prohibit a Canaanite servant woman to a Jewish servant man and the Torah only requires lashes for relations with a servant woman who was designated for another man, as was discussed in halacha 3:13.

Hilchos Issurei Biah 12:13

One should not treat this matter casually just because it doesn’t incur lashes at the Biblical level. This also causes one’s child to be turned away from following God because the child of a servant woman is a servant and not a member of Israel. One therefore profanes his seed by fathering servants. Onkelos included relations with a male servant and relations with a female servant in the prohibition against promiscuity (Deuteronomy 23:18).